Knockdown of astrocyte elevated gene‑1 inhibits growth through suppression of IL‑6 secretion in HepG2 human hepatoma cells

Deng,Huan; Zhou,Zhenzhen; Tu,Wei; Xia,Yujia; Huang,Huanjun; Tian,De'an

doi:10.3892/ol.2013.1645

Knockdown of astrocyte elevated gene‑1 inhibits growth through suppression of IL‑6 secretion in HepG2 human hepatoma cells

Authors:
- Huan Deng
- Zhenzhen Zhou
- Wei Tu
- Yujia Xia
- Huanjun Huang
- De'an Tian
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Affiliations: Department of Gastroenterology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 P.R. China
Published online on: October 29, 2013 https://doi.org/10.3892/ol.2013.1645
Pages: 101-106

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Abstract

Astrocyte‑elevated gene‑1 (AEG‑1) has been reported to be associated with cancer progression in various types of human cancers, including liver cancer. However, to date, the molecular mechanism of AEG‑1 action on the growth of liver cancer cells has been poorly elucidated. The present study aimed to investigate the effect of AEG‑1 on the proliferation and apoptosis of liver cancer cells and the role of IL‑6 in this process using the HepG2 human hepatoma cell line. shRNAs targeting AEG‑1 were used to silence the expression of AEG‑1. The effects on cell growth were detected by 3‑(4, 5‑dimethylthiazol‑2‑yl)‑2, 5‑diphenyltetrazolium bromide, colony formation and cell cycle assays. Apoptosis was analyzed by flow cytometry. The expression of IL‑6 was examined by quantitative polymerase chain reaction and enzyme‑linked immunosorbent assay, and the phosphorylation of Stat3 was detected by western blotting. AEG‑1 knockdown was observed to induce cell proliferation inhibition and apoptosis through the suppression of IL‑6 secretion. Stat3, a downstream target of IL‑6 signaling, was suppressed in the AEG‑1‑silenced cells and target genes, including Bcl‑2 and crystalin, αB, which are associated with cell survival, were downregulated. Overall, the findings suggest that aberrant AEG‑1 expression promotes the growth of HepG2 liver cancer cells, contributing to the progression of liver cancer, which may partly be mediated by IL‑6 signaling.

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